Re: [Qemu-devel] [v2][PATCH 2/5] hw:pci-host:piix: split i440fx_init

["Chen, Tiejun" <tiejun.chen@intel.com>]

On 2014/7/31 23:47, Michael S. Tsirkin wrote:
> On Thu, Jul 31, 2014 at 08:10:53PM +0800, Chen, Tiejun wrote:
>> On 2014/7/31 18:12, Chen, Tiejun wrote:
>>> On 2014/7/31 17:53, Michael S. Tsirkin wrote:
>>>> On Thu, Jul 31, 2014 at 05:26:41PM +0800, Chen, Tiejun wrote:
>>>>> On 2014/7/31 17:10, Michael S. Tsirkin wrote:
>>>>>> On Thu, Jul 31, 2014 at 02:31:36PM +0800, Tiejun Chen wrote:
>>>>>>> We'd like to split i440fx_init and then we can share something
>>>>>>> with other stuff.
>>>>>>>
>>>>>>> Signed-off-by: Tiejun Chen <tiejun.chen@intel.com>
>>>>>>
>>>>>> I think this is too much work for very little benefit.
>>>>>> Just pass const char *type to i440fx_init.
>>>>>
>>>>> You know we will introduce that faked PCIe device represented that PCH
>>>>> later,
>>>>
>>>> Later when? On top of this patch series? Would like to see it all
>>>> before applying this ...
>>>
>>> I will send this with other IGD stuff after this series is fine to you
>>> since its just creating a simple PCIe device.
>>>
>>> I think you should know this whole story since as you guys discussed we
>>> don't fix that PCH at 1f.0. So it may be like this,
>>>
>>> static int create_pseudo_pch_isa_bridge(PCIBus *bus, XenHostPCIDevice
>>> *hdev)
>>> {
>>>
>>>      struct PCIDevice *dev;
>>>
>>>      char rid;
>>>
>>>      /* We havt to use a simple PCI device to fake this ISA bridge
>>>       * to avoid making some confusion to BIOS and ACPI.
>>>       */
>>>      dev = pci_create(bus, -1, "pseudo-intel-pch-isa-bridge");
>>>
>>>      qdev_init_nofail(&dev->qdev);
>>>      pci_config_set_vendor_id(dev->config, XEN_SUBSYSTEM_ID));
>>>                          ^
>>>                  I don't remember this exactly.
>>>      pci_config_set_device_id(dev->config, hdev->device_id);
>>>
>>>      return 0;
>>> }
>>>
>>>>
>>>>> so how to distinguish them? Are you saying I should check the type
>>>>> like this?
>>>>>
>>>>> if(Xen-Type)
>>>>> {}
>>>>> else
>>>>> {}
>>>>>
>>>>
>>>> No! Put the code in init function for the respective class,
>>>> pass type as an argument:
>>>
>>> If you mean we don't introduce any "if/else", I still don't understand
>>> how to insert such that function above, could you show this exactly?
>>>
>>
>> I think I can do this inside that into
>> xen_igd_passthrough_pc_machine_pci_bus_init(). There, we can just follow
>> pci_bus = i440fx_init() since create_pseudo_pch_isa_bridge() just needs
>> pci_bus as a parameter.
>>
>> Thanks
>> Tiejun
>
> Do it in xen_igd_i440fx_class_init: constructor for your class.
> This device is not hot-pluggable right?
> If so I would prefer not to make this xen specific.
> Instead, find the device and tweak the id when you
> initialize the card.

Michael,

I mean in v3 patches series to do something like,

xen_igd_passthrough_pc_machine_pci_bus_init()
{
	if (pci_enabled) {
		pci_bus = i440fx_init();
		create_pseudo_pch_isa_bridge()
	}

Thanks
Tiejun